Modeling the receptivity of an air jet to transverse acoustic disturbance with application to musical instruments.

A simple analytical model for the interaction between a plane jet issued from a flue and a transverse acoustic disturbance is developed in this paper. The model is inspired by direct flow simulation results confronted to experimental data. The interaction is expected to take place in the vicinity of the separation points of the jet. The influence of the detailed geometry of the channel end on the jet receptivity is discussed, and more specifically the chamfer geometries found in flute-like musical instruments. The simplified model explains quite well the difference between the jet response of a flue with square edges compared to a chamfered flue exit. The effect of rounded, lip-like flue exit is not well captured by the model.

Economic evaluation of adherence to treatment guidelines in nonintensive care pneumonia.

Guidelines have been developed to improve the treatment of community-acquired pneumonia (CAP) but information regarding their influence on costs is lacking. The aim of the present study was to conduct a cost-effectiveness analysis of CAP treatment from the hospital perspective when adhering to Spanish guidelines. A prospective cohort study was performed in 271 patients with CAP admitted to a tertiary-care hospital, not needing intensive care. Collected data included patients' characteristics, comorbidity, initial risk class, resource use (medication, blood and microbiological analyses, and radiology) and economic data. Antimicrobial treatment was recorded as adherent or nonadherent to Spanish guidelines. Outcome measures were mortality and readmission at 30 days. The median cost for adherent treatment was 1,665.5 versus 1,710.5 Euros for nonadherent treatment. Mortality and readmission were 10% and 2.1% for adherent treatment versus 13.6% and 6.2% for nonadherent treatment. The cost-effectiveness ratio was 2,277 Euros per expected cure for patients treated according to the guidelines and 2,567 Euros per expected cure for the nonadherence group. The incremental cost-effectiveness ratio showed that adherence to treatment guidelines saved 1,121 Euros per patient cured compared with nonadherence. The sensitivity analysis demonstrated that the findings were robust. An antimicrobial treatment according to guidelines is the dominant alternative due to its cost-effectiveness.

Correlates of wellbeing of spousal and children carers of disabled people over 65 in Spain.

BACKGROUND: The aim of this study was to evaluate the associations between carer's wellbeing and stressors and to assess if these associations are different for spousal and children carers of disabled elderly. METHODS: Information was collected by home interviews of a population sample of carers (N = 195), who were providing assistance in activities of daily living to a community-dwelling population over 65. Associations between indicators of wellbeing (number of depressive symptoms, number of physical symptoms, self-perceived health and life satisfaction) and caring stressors were examined, controlling for carer's socio-economic characteristics and health status. Hierarchical logistic regressions were used to fit the data. Religion and social support were included as resources and spousal and children differential associations were tested. RESULTS: The four indicators of wellbeing are moderately correlated, indicating a common underlying concept. Spousal carers have lower socio-economic status, poorer health and lower levels of wellbeing than children carers. However, children carers bear a significantly greater burden. In the multivariate analysis of the associations between wellbeing and stressors, the similarities between spouse and adult child carers are more striking than the differences. Emotional support was consistently associated with higher levels of wellbeing while the associations of religiosity and instrumental support with wellbeing did not reach statistical significance. CONCLUSION: As formal care services are being developed in Spain, their ability to work in a supportive way with family networks should be taken into account. Research should be carried out on patterns of formal care interventions that use the resources in the natural support network of the family.

Loss to follow-up in a longitudinal study on aging in Spain.

The objectives of this study were to describe follow-up dynamics in a longitudinal study on aging conducted in Spain between 1993 and 1997, and to identify the demographic, behavioral and health characteristics of persons who would later refuse to continue participating, move out of the area or be hard to locate (i.e., become lost to follow-up subjects). Data from the 1993 baseline survey were used to predict the probabilities of being lost to follow-up in the 1995 and 1997 waves. Structural multiple logistic regressions were fitted and mean probabilities were estimated to identify patterns of loss to follow-up. After 4 years, 52% of baseline participants remained in the study, 24% had died, 17% refused to continue participating, and 8.7% were impossible to locate. In the multivariate analysis, advanced age and living alone were independent predictors of loss to follow-up, and none of the health status variables remained significant. However, participation status in previous waves and the number of nonresponse items were strong independent predictors of further non-participation. Our results suggest that an attitude against participation in surveys may be an independent predictor of losses to follow-up and efforts should be made to retain this subgroup of the population in the study. Further research on reasons why people are unwilling to participate in surveys and strategies to retain people in longitudinal studies is needed.

[Family caregivers of people with neurodegenerative disease: profile, contributions, and impact of care]. / Cuidadores familiares de personas con enfermedad neurodegenerativa: perfil, aportaciones e impacto de cuidar.

OBJECTIVE: To analyse the informal system of caring for people with neuro-degenerative disease: what it consists of and the characteristics of main carers, the type of care given, and the consequences for the main carer of assuming these functions. DESIGN: Descriptive cross-sectional study conducted by means of a home-filled questionnaire. SETTING: Autonomous Community of Andalusia. PARTICIPANTS: 72 main carers of someone with neuro-degenerative disease, chosen from a sub-sample of 1000 homes in which at least one dependent person lives and receives care from a member of his/her family or social network with whom he/she resides. This sub-sample was based on a random sample of 3160 Andalusian homes stratified proportionately according to province and size of dwelling. MAIN RESULTS: In 86.1% of the 72 homes polled, health care was provided only by the informal system network. In over half the homes, care was provided by just one person, the main carer. The main carer was usually a woman (87.4%), with an average age of 54.52, house-wife and close family member of the sick person. In our study the beneficiaries of care had an average age of 77.63, a low level of autonomy in daily activities, and had had a neuro-degenerative disease for an average of 8.16 years. The main kinds of care provided in the home for people with neuro-degenerative disease were help in instrumental activities, care related to daily activities, observation/company and supervision of medicines. Main carers believed that undertaking this work had seriously affected their health (72.2%), the use they made of their time (84.7%), their social life (83.3%) and their economic position (44.4%). CONCLUSIONS: People with neuro-degenerative disease make considerable demands on health care provision, which is mainly covered at home by the immediate family network. In most cases this network consists of just one person, the main carer, on whom falls the entire burden of care. The assumption of this role directly affects the health of a large number of carers, as well as other areas of their lives, in particular the possibility of conducting a social life and using their time for themselves or for activities other than caring.

Pediatric stress fractures.

Stress fractures in children are uncommon. This report describes the findings of 8 cases in 6 children. One patient had 3 stress fractures: 2 consecutive midshaft stress fractures of the same tibia associated with one of the fibula. Signs and symptoms may be misdiagnosed as malignant tumors or osteomyelitis. Serial radiographs and computed tomography scans are the key to the diagnosis, although bone scan and magnetic resonance imaging can be helpful. Biopsy is unnecessary and might even be misleading.

Development of simple cognitive function measures in a community dwelling population of elderly in Spain.

OBJECTIVE: To develop and assess the consistency and validity of simple cognitive function measures for an elderly population with low levels of formal education for use in a longitudinal study of dementia. METHODS: Data were from the population longitudinal study 'Growing old in Leganés' (Spain). In 1993, a random sample of 1540 people over 65 was drawn from the City Roll of Leganés from which 1284 (83%) were successfully interviewed. Measures of memory and orientation were based on the SPMSQ (Short Portable Mental Status Questionnaire), the Barcelona test and the short story from EPESE (Established Populations Epidemiologic Studies of the Elderly). Non-response to a test item was coded as an error. Internal consistency was assessed by factor analysis and Cronbach's alpha. Construct validity was examined with multiple linear regressions of the proposed measurements on variables chosen from the existing literature on cognitive function. RESULTS: Two factors, memory and orientation, emerged from the factor analysis. Internal consistency of the proposed indexes for memory and orientation was acceptable. Memory and orientation scores were summed into one summary index of cognition. Associations between covariates and both cognitive indexes were in the expected direction. Among those highly functional, orientation was influenced by illiteracy due to higher error rates in the time orientation items based on dates; however, memory and summary scores were not significantly different by literacy status. A large proportion of the variance in IADL was explained by the memory and orientation measures. CONCLUSION: The memory and orientation indexes are valid and reliable measurements of cognitive function for use in a population of community dwelling elderly with low levels of formal education and high rates of illiteracy.

[The short-term effects of air pollution on mortality: the results of the EMECAM project in the city of Huelva, 1993-96. Estudio Multicéntrico Español sobre la Relación entre la Contaminación Atmosférica y la Mortalidad]. / Efectos a corto plazo de la contaminación atmosférica sobre la mortalidad: resultados del proyecto EMECAM en la ciudad de Huelva, 1993-96.

BACKGROUND: The objective of this study was to estimate the relationship between the levels of air pollution and the daily mortality in the city of Huelva for the 1993-1996 period using the EMECAM methodology. METHODS: The number of daily deaths for all causes except external ones, the death rate of those over age 69, due to diseases of the circulatory system and for respiratory diseases were used as rate indicators. Four pollutants--SO2, PM10, NO2 and CO--were analyzed, the daily levels of which were furnished by the air pollution monitoring network in Huelva. Autoregressive Poisson regression models were constructed controlling by tendency, seasonality, temperature, humidity, flue and events out of the ordinary. RESULTS: For the mortality rate for all causes, a significant association impact was found to exist for the NO2 for the entire period (RR10 microgram/m3: 1.0414; CI95%: 1.0047-1.0794) and for the particles (PM10) for the cold half of the year (RR10 microgram/m3: 1.0358; CI95%: 1.007-1.0722). For the mortality in people over age 69, a significant relationship was found to exist for SO2 throughout the entire period (RR10 microgram/m3: 1.0606; CI95%: 1.0020-1.1227). A significant relationship to the mortality from respiratory disease particles (PM10) was found to exist for the cold half of the year (RR10 microgram/m3: 1.1412; IC95%: 1.0300-1.2644). There was no association of contaminants with cardiovascular mortality; also there was no association between levels of CO and mortality indicators. CONCLUSIONS: In Huelva, significant relationships have been found to exist between the current levels of air pollution resulting from particles, SO2 and NO2 and the daily mortality. The impact of these pollutants on the mortality is coherent with scientific literature, although in the case of Huelva, the extremely small number of daily deaths due to its small population and other factors limit the consistency thereof.

[The short-term effects of air pollution on mortality. The results of the EMCAM project in the city of Seville, 1992-1996. Estudio Multicéntrico Español sobre la Relación entre la Contaminación Atmosférica y la Mortalidad]. / Efectos a corto plazo de la contaminación atmosférica sobre la mortalidad. Resultados del proyecto EMECAM en la ciudad de Sevilla, 1992-1996

BACKGROUND: As part of the EMECAM Project, the objective of this study is that of assessing the impact of air pollution on the daily mortality in Seville throughout the 1992-1996 period. METHODS: During the 1992-1996 period, readings were taken daily of the amounts of SO2, particles in suspension (PM10) and NO2 present in the air in the city of Seville, in addition to the number of deaths daily due to different causes. For analyzing this data, a multivariable Poisson regression model was used for modeling each one of the causes of death in terms of the air immission readings, controlling other confusion-causing variables. RESULTS: A relationship was found to exist between the rises in the NO2 levels and the daily death rate throughout the months of May to October. For each 10 micrograms/m3 rise, the risk of death or all causes showed a 2% rise, the same rise in the NO2 levels leading to a 3% rise in the risk of death resulting from cardiovascular diseases. CONCLUSIONS: A relationship exists between the levels of NO2 air pollution and the daily death rate in Seville. The findings provide scientific knowledge and information which can be of use for preventing the impact of air pollution on human health.

Value of the polymerase chain reaction assay in noninvasive respiratory samples for diagnosis of community-acquired pneumonia.

We studied the causes of community-acquired pneumonia (CAP) in 184 patients. Microbiologic evaluation included sputum examination, blood culture, assessment of acute and convalescent antibody titers for Legionella pneumophila, Mycoplasma pneumoniae, Chlamydia pneumoniae, Coxiella psitacci, Coxiella burnetii and respiratory viruses, polymerase chain reaction (PCR) assays for M. pneumoniae and C. pneumoniae in throat swab, and PCR assay based on the amplification of pneumolysin gene fragment in sera. The causative pathogen was identified in 78 patients (Streptococcus pneumoniae, 44; M. pneumoniae, 26; C. pneumoniae, 1; others, 7). S. pneumoniae was detected in serum by the PCR assay in 41 patients, five of whom also had a positive blood culture. PCR assay was negative in two patients with positive blood culture for S. pneumoniae. C. pneumoniae was detected by PCR in nine patients, but only one showed seroconversion. M. pneumoniae was detected by PCR in only three patients (two without seroconversion). The diagnosis of pneumonia caused by S. pneumoniae was five times greater using PCR in serum than with blood culture. Detection of C. pneumoniae by PCR without fulfilling criteria for acute infection may be considered a prior infection. The PCR assay for the diagnosis of M. pneumoniae has a lower sensitivity than serologic methods.

[20210G/A mutation of prothrombin gene in a patient with deep venous thrombosis ad pulmonary embolism without other risk factors of thrombosis]. / Mutación 20210G/A del gen de la protrombina en un paciente con trombosis venosa profunda y embolia pulmonar sin otros factores de riesgo trombótico.

A new genetic anomaly predisposing to venous thrombosis was described in 1996, namely the transition of guanine (G) to adenine (A) at position 20210 in the 3-untranslated region of the prothrombin gene. This mutation is associated with high levels of plasma prothrombin and increased risk of thrombotic events in the venous system. We report the case of a man who, lacking known risk factors for thrombosis, suffered a massive pulmonary embolism and deep venous thrombosis in both lower legs. Thrombophilic analysis confirmed that the patient and close relatives were carriers of the heterozygotic 20210G/A variant of the prothrombin gene. Two relatives with the genetic defect had also suffered some type of deep venous thrombosis.

[Treatment of asthmatic crises at a hospital emergency service. Are the protocols followed?]. / Tratamiento de la crisis asmática en un servicio de urgencias hospitalario. Se cumplen las normativas?

Improper assessment and treatment of asthma attacks have been identified as causes of increased morbidity and mortality: several pneumological societies have therefore created and published guidelines for facilitating decision making and for preventing unnecessary failures of therapy. The objective of this study was to examine emergency department compliance with such guidelines in our hospital, comparing the performance of pneumologists and other specialists. We reviewed the records of 117 patients treated for acute asthma attacks in 1994 (87 women and 30 men, mean age 46 years); 37 patients were treated by pneumologists and 80 by other specialists. The two physician groups differed significantly with respect to initial assessment of severity, particularly in the recording of vital signs (p < 0.05) and in the examination of some signs such as the use of accessory musculature (38% versus 10%, for pneumologists and other specialists, respectively) or the presence of cyanosis (81% versus 55%). Other factors associated with risk of death were noted only occasionally. Peak flow meters were used with only 5 patients, all examined by pneumologists; on the other hand, arterial blood samples for gasometric measurements were taken from 97%, although only 24% met the criteria stipulated in the guidelines. Treatment evaluated against the guidelines was incorrect in 24%, with no significant differences between pneumologists and other specialists. We conclude that: 1) the emergency clinical assessment and treatment of patients presenting with acute asthma attack is inadequate for a large proportion of patients, as the recommendations of consensual guidelines are habitually ignored, and 2) although there are differences in the management of these patients by pneumologists and other emergency room specialists, the former do not generally do a better job of following the guidelines.